The safety of the UK's Trident nuclear weapons is to be discussed in Parliament today, after the SNP secured a debate slot.
The party wants to press UK government on recent claims made by a whistleblower concerning the state of the weapons programme.
Able Seaman William McNeilly, 25, caused a manhunt after he published an 18-page report online containing a series of allegations about nuclear submarines based at Faslane, which he called a "disaster waiting to happen".
Alex Salmond, the party's foreign affairs spokesman, said: "Trident is a key issue for people in Scotland. It is bad enough that Scotland is forced to house these weapons of mass destruction but these alleged breaches of security are deeply worrying - there must be absolutely no complacency."
The SNP will make "a positive case" for keeping the UK in the European Union, one of its new MPs has told Parliament.
In his maiden speech to the Commons, Stephen Gethins, MP for North East Fife, also said that his party would try and get as many people voting as possible.
He said: "We want to look at a positive case, even look at some areas where we could be deepening our relationship with our European partners."
He added that "the Scottish referendum provided many lessons", especially "including as many of our citizens as we possibly can in a debate about the future of our respective nations".
Ukip leader Nigel Farage has criticised the wording of the question that will be asked at the EU referendum.
Because David Cameron "is opting to give the pro-EU side the positive 'Yes'", he said, "suggests strongly that his negotiations are so much fudge".
"He has already decided which way he wants the answer to be given, without a single power repatriated."
Details of the In/Out referendum will be presented to Parliament in a Bill this morning.Read the full story ›
David Cameron's pledge to abolish the Human Rights Act and replace it with a British bill of rights was conspicuously absent from the Queen's Speech.
ITV News' Deputy Political Editor Chris Ship reports on why the PM decided his plans for abolishing the Act needed more work.
Scotland Yard said three arrests had been made before 7pm in relation to the anti-austerity demonstration which took place to coincide with the Queen's Speech and the State Opening of Parliament.
A 17-year-old youth was arrested on suspicion of assault.
A man, whose age has not been given, was arrested on suspicion of violent disorder and possession of an offensive weapon.
Police also arrested a 45-year-old man who was wanted on suspicion of violent disorder in relation to an incident in Whitehall on May 9th.
Ukip's only Member of Parliament Douglas Carswell has said he genuinely feared for his life after being surrounded by a "lynch mob" of anti-austerity protesters as he tried to leave Westminster following the Queen's Speech.
Am fine. Bit shaken. As an MP I will always use public transport and I do not want to live in a society when politicos don't
Mr Carswell said the group that shouted abuse at him as he waited for a bus appeared to have "pretty murderous" intent before he was escorted by officers into the back of a police van as demonstrations turned nasty.
He was caught up in one of several violent flashpoints as he waited for public transport not far from the House of Commons.
A total of 26 new Bills were laid out in the Queen's Speech today but at the heart of it was confirmation of an in/out referendum on Britain's membership of the EU.
David Cameron said it was also a programme for working people, with promises of tax freezes and more free childcare.
ITV News' Political Editor Tom Bradby reports on the pomp and pageantry:
Liberal Democrats in Alistair Carmichael's Orkney and Shetland constituency are backing the former Scottish Secretary amid a police investigation into his election smear tactics and a growing online campaign to have him removed.
Carmichael leaked an unsubstantiated memo claiming Nicola Sturgeon, the Scottish National Party (SNP) leader, had expressed support for the Conservatives, and initially denied any responsibility for the leak.
Local party members have voiced disappointment at Carmichael's conduct, but urged his constituents to give him "a fair hearing" rather than giving in to "mob rule" and the "increasingly personal and unpleasant political motivation of the SNP and the Yes campaign".
The members agreed that Alistair [Carmichael] has rightly taken full responsibility and has apologised to all concerned, not least to the people of Orkney and Shetland ... and he retains the full confidence of the executive.
Scuffles have broken out between police and protesters at an anti-austerity demonstration being held in Downing Street to coincide with the Queen's Speech, ITV News' Emma Murphy reports.
The 'End Austerity Now' demonstration has been organised by The People's Assembly Against Austerity.